Drill.



W. H. CRITTON. DRILL.l APPLIUATION FILED 00T.]0, 1911.

1,030,387. mannedA June 25, 1912.

Nrrnn STATES @PATENT OFFICE.

WILLIAM H. CRITTON, OF FELLOWS, CALIFORNIA.

DRILL.

Specification of Letters Patent.

Application led October 10, 1911.

Patented June a5, 1912.

Serial No. 653,877.

To all whom t may concern.'

Be it known that I, WILLIAM H. CRIT- 'roN, a citizen of the UnitedStates, residing at Fellows, in the county of Kern and State ofCalifornia, have invented new and useful Improvements in Drills, ofwhich the .following is a specification.

curing means being also provided for preventing the accidentalseparation of the bit or boring tool from said stern.

It is also an object of the invention to provide a drill bit with acarrying stem which is normally secured thereto by a screw joint,

the said stem also carrying a reinforcing sleeve or coupling adapted tocover the joint between said parts, the said coupling being adapted toprevent the bit from becoming separated from said stem even though itshould be unscrewed therefrom or be broken therefrom.

In the accompanying drawing forming a part of this specification, Figurel is a side elevation of a drill point or bit and the stem carrying thesame, the coupling means at the joint between the parts being partiallybroken away and shown in section. Fig. 2 is a longitudinal sectionalcentral View through the device.

The details and features of the invention will now be more particularly'described, reference being had to the said drawing in which 5 indicatesthe body of a drill usually of the ordinary type and 6 a stern adaptedto be secured thereto. The blt illustrated in the drawing is of the shtail type having cutting points 7 and is made hollow having a centralpassage 8 and d1- verging outlets 9 leading therefrom. The said bit isalso formed with a screw threaded socket 10 adapted to receive a vscrewthreaded projection 11 upon the adjacent end of the stem 6. The saidstem 6 is made hol- 1low so as tobe capable of delivering liquidsannular thickened ange. A sleeve or couphng 12 lis adapted to be slippedupon the upper end of the said stem 6 and is formed l with an annularflange 14 extending inwardly from lts upper end and arranged to -fitagainst the shoulder 12 upon saidstem.

The lower end of the coupling 13 is interiorly threaded and vadapted toengage exterior threads 15 formed upon the upper end of the bit. Theupper end of the stem is also provided with screw threaded projection.16 adapted to engage a correspondingly threaded socket 17 formed in theadjacent end of a short stem coupling section 18. The said stem couplingsection 18 is formed with an annular shoulder 19 for limiting the upwardmovement of the coupling or sleeve 13 when it is disconnected from thebit. The upper end ofsaid stem coupling section 18 is also formed with ascrew threaded projection 20 adapted to fit the usual drill piping bywhich the drill is lowered into the well and turned for boring the saidwell. The said section 18 is also hollow so that water for clearing thewell of cuttings can be delivered from the piping carrying the drill,through the said stem section and stem'and through the openings in thebody of the bit to points near the cutting points of said bit.

The use of the sleeve or coupling 13 in connection with the shoulderedstem is an important feature of the l invention since the said couplingsleeve not only strengthens the parts as they are ordinarily connectedbut in the event of the stem 6 becoming unscrewed from the bit 5 asshown in Fig. 2, the said bit cannot be lost in the well since it willbe held upon the stem by the said coupling. The same thing is true ifthe stern becomes broken from its connection with the said bit asfrequently occurs. It will be seen thatin such case it is only`necessary to elevate the drill mechanism from the well in order toreplace the bit in its normal position as shown in Fig. 1 or if thestern be broken to put in a new stem.

It will be understood that the scretv larger than the opening at thecontractedI end of the coupling or sleeve 13 or that the said stem bemade in two parts so that it may be separated between the enlarged orshouldered portions thereof. The manner et' forming the stem and bitmakes it possible to secure a very strong and rigid connection betweenthe parts and also prevents the possibility of loosing the bit or drillpoint in the Well, which is frequently a source of great annoyance anddiieulty and sometimes renders it impossibleyto go forward with thedrilling of the Well. The elongated stem employed also yprevents thedrill from becoming tipped in the bore of the well. The connectionbetween the bit and the coupling 13 is also such that the said bit willnot become twisted in the well even though the stem be broken, orunscrewed from the said bit.

What I claim is A drill mechanism comprising a hollow stem having upperand lower sections re- .annular limiting shoulders formed thereon,

a coupling sleeve adapted to be slippedl l upon said hollow stem whenthe sections are separated, the annular limiting shoulders preventingthe coupling from slipping from the stem, a bit having a neck portionadapted to be screwed into the lower end of said coupling, the said-bitalso having a socket adapted to be screwed onto the lower end of saidstem, the structure being such that the coupling will prevent the lossof the bit if it becomes unserewed or broken from the stem.

In witness that I claim the foregoing I have hereunto subscribed my namethis 30th day of September, 1911.

WILLIAM H. CRITTON. vWitnesses E. A. REARDON, H. K. BACON.

